Ships and similar vessels are moored in ports everyday around the world. When a ship is moored at a terminal this usually involves guiding the ship in towards the terminal at a low speed. Tugs are often used to assist this. However, even at such low speeds, the large mass of a ship creates a high inertia. This can result in damage to either the terminal or the ship or both. For this reason buffer elements, commonly known as fenders, are used to provide a resilient shock absorbing interface for absorbing the energy of an approaching vessel.
Examples of fenders include large tyres, rubber bricks, timber cladding, and the like. Typically, once a ship has been moored at a terminal, it is held against the fenders to prevent it from moving around under the forces of wind, tides and any swell.
Mooring robots are known for use in mooring ships to terminals. PCT publication WO 2002/090176 entitled “Mooring Robot”, which is incorporated herein by reference, discloses a mooring robot including suction cups for engagement with the freeboard of a ship. The mooring robot can position the suction cups within a 3-dimensional operating envelope. An arm linkage is provided for extending and retracting the suction cups in the transverse direction. Using such mooring robots, a ship can be secured to a terminal and external forces acting on the ship can be counteracted by the mooring robots, at least so some extent. However, in order for the suction cups on such a mooring robot to engage and hold the ship, the ship must be in a relatively stable position, and must have been brought within the range of movement of the suction cups.
If a ship is moving towards the terminal quickly, or if it is oscillating significantly (such as due to the external forces mentioned above) difficulties can arise in engaging of the ship with a suction cup.
As shipping lanes and ports become more congested, it would be advantageous to be able to provide automation of the mooring of commercial and passenger shipping in order to streamline the process and potentially reduce the time that a ship is moored at the terminal. This could offer the advantage of increased utilisation of the terminal.
Further, as commercial shipping increases, so do the size of commercial ships. One effect of this is that these ships become more difficult to control during the mooring process, since it is not always immediately apparent to the captain or pilot of such a ship where the ship is in relation to the terminal to be moored at. Nor how a particular ship reacts during the mooring process, to the external forces acting on the ship. Additionally, prevailing weather and tide conditions may make the mooring of large commercial ships difficult and possibly dangerous. Large forces that a ship can exert on objects around it, can for example result in damage to the mooring terminal and/or the mooring robots.
It may be an object of the present invention to provide a mooring system and/or method of mooring a vessel which overcomes or at least ameliorates some of the above mentioned disadvantages, or which at least provides the public with a useful choice.
It may also be an object of the present invention to provide a mooring system and related method that can determine the position and/or velocity of an incoming vessel to allow for a mooring device to be controlled to reduce the likelihood of damage from incorrect operation and/or excessive or undesirable vessel velocities and/or to at least provide the public with a useful choice.
In this specification, where reference has been made to external sources of information, including patent specifications and other documents, this is generally for the purpose of providing a context for discussing the features of the present invention. Unless stated otherwise, reference to such sources of information is not to be construed, in any jurisdiction, as an admission that such sources of information are prior art or form part of the common general knowledge in the art.